Large Tankers carrying CORK?! 10 torps and no sinking

[Chock]

Just been reading up on this a little to see how likely it is that a cargo would actually contribute to the ship's demise, and where petrol is concerned, unless it gets a mix of air and gas in the right proportions, it is actually fairly hard to ignite, and since the explosion happens underwater for torpedo hits, that seems to explain a fair bit.

Incidentally some years ago, this factor was the catalyst for an attempt to make AVGAS less flammable in an accident, by causing it to gel upon receipt of a shock to prevent it from 'misting' and reaching an explosive fuel/air mix during the impact of an aeroplane crash.

Back in world war two however, there are numerous instances of tankers resolutely refusing to explode despite containing what would seem to be very flammable cargoes, the most famous instance being the tanker San Demetrio (built 1938, i.e. modern by WW2 standards), which was attacked by the German warship Admiral Scheer while crossing the Atlantic in 1940.

Despite being hit repeatedly by the 11 inch guns of the Scheer, set ablaze, and abandoned by her crew, the blazing tanker was re-boarded two days later, when part of the crew who had not been rescued decided that the risk involved was better than chancing things in their lifeboat. They put out the fires, repaired the steering gear and eventually got the damaged tanker under weigh to Ireland and then on to the Clyde. Upon arrival, it was found that she had only lost 200 tons of her 12,000 ton cargo of aviation fuel. The crew who re-boarded her were actually awarded salvage rights to her and received quite a large monetary reward for their efforts.

The event is dramatised in the 1943 British flag-waver movie 'San Demetrio, London', which coincidentally was screened on TV in the UK the other day. It is also the basis for the 1959 children's adventure novel 'The Lame Duck', by Richard Armstrong. And, it provided the inspiration for an incident in the movie 'Das Boot', where a tanker that refuses to sink is finished off by the sub many hours after their initial attack, only to reveal that the crew are still aboard.

Unfortunately for its crew, the repaired San Demetrio was eventually sunk by a torpedo from U-404 in 1942, so the resilience of tankers against torpedoes doesn't always hold true it seems.

Other cargoes noted for making a ship difficult to sink, include wool and cotton. Historically, ships carrying these cargoes would be placed on the outside edges of convoys if practicable, to further screen more vulnerable ships. And this was often possible, since their cargoes, while large in volume, were generally lighter, making the ships carrying such goods better able to manouever on the outside edges of a convoy, where they would often have to speed up to maintain position in a zig-zag.
It's also one of the reasons why ships likely to be carrying that sort of thing were generally better armed than a lot of other merchants.

Whether any of the historical disposition and make-up of convoys is modeled in SH3 or SH4 to any degree of real accuracy, is debatable however, and the Japanese certainly lagged behind their European and American counterparts when it came to experience with convoy operations, the UK having already perfected much of it during WW1.

[ccruner13]

just to throw this out there....there was a salvage of pearl harbor thing on the history channel just now and one torpedo went under the hull of a boat sitting next to some other battleship or something and when the torpedo detonated against the bb the blast crinkeled the hull of the next door ship and it rolled over and sunk. so the 7 torpedos i shot into the large old split freighter seem excessive considering it still hasnt sunk

[nattydread]

I put 5 fish into a huge ocean liner. 3 starboard 2 port running at 15-20ft. Thge 5th had her on fire but she kept steaming at the same speed. My last two torps pre-detonated even though atleast one was set for contact fuses...go figure.

I aborted the attack to keep from going into shallow water and a minefield. The end-around at mid-day right off the coast would have been a bit iffy too!

Either way 12 torps used up with no kill (2-3 sure misses, the other pre-dets I think...I dont have the camera enabled).

[Galanti]

Originally Posted by nattydread

I put 5 fish into a huge ocean liner. 3 starboard 2 port running at 15-20ft. Thge 5th had her on fire but she kept steaming at the same speed. My last two torps pre-detonated even though atleast one was set for contact fuses...go figure.

I aborted the attack to keep from going into shallow water and a minefield. The end-around at mid-day right off the coast would have been a bit iffy too!

Either way 12 torps used up with no kill (2-3 sure misses, the other pre-dets I think...I dont have the camera enabled).

As someone (Beery or Ducimus?) pointed out elsewhere, duds are modelled somewhat squirrelly in this game. I've noticed myself I only get the 'torpedo was a dud message' when I'm below periscope depth and my hydrophones are working. Also, graphically, duds often use the same sound and graphics as real hits.

Data in the torpedoes_sim file seems to suggest that some particular types of duds are triggered 1.5m from the target, which would logically look to the skipper as a solid hit. It's possible that this is leading many people to believe that many marus are soaking up far more hits than is possible.

I'm not saying the damage model is perfect by any means. I hear players boasting of sinking Yamato with 4 torps, or CAs and CVs with single hits, which would really stick in my craw in career mode.

Edit: I found Beery's post. it's a ways down, so here's his observation:


One thing to be aware of is that the game models some duds in a rather weird way: some torpedoes will impact a ship and they'll appear to explode, but they have no effect on the enemy ship at all. You can only see the non-effect of these torpedoes if you have the full 3D damage graphics checked in the graphics options - they leave no hole in the ship's hull.

Because of the above many players are complaining of torpedoes that explode but do no damage. I think these were intended to be 'contact duds' but the devs forgot to remove the explosion graphics and the sound.

http://www.subsim.com/radioroom/show...=113031&page=4

[Redwine]

Originally Posted by Galanti

As someone (Beery or Ducimus?) pointed out elsewhere, duds are modelled somewhat squirrelly in this game. I've noticed myself I only get the 'torpedo was a dud message' when I'm below periscope depth and my hydrophones are working. Also, graphically, duds often use the same sound and graphics as real hits.

Data in the torpedoes_sim file seems to suggest that some particular types of duds are triggered 1.5m from the target, which would logically look to the skipper as a solid hit. It's possible that this is leading many people to believe that many marus are soaking up far more hits than is possible.

I'm not saying the damage model is perfect by any means. I hear players boasting of sinking Yamato with 4 torps, or CAs and CVs with single hits, which would really stick in my craw in career mode.

Edit: I found Beery's post. it's a ways down, so here's his observation:


One thing to be aware of is that the game models some duds in a rather weird way: some torpedoes will impact a ship and they'll appear to explode, but they have no effect on the enemy ship at all. You can only see the non-effect of these torpedoes if you have the full 3D damage graphics checked in the graphics options - they leave no hole in the ship's hull.

Because of the above many players are complaining of torpedoes that explode but do no damage. I think these were intended to be 'contact duds' but the devs forgot to remove the explosion graphics and the sound.

http://www.subsim.com/radioroom/show...=113031&page=4

Your comment is very apreciated and useful...

It is very important to have your comments present.

If not remember bad, into .sim as you wrote, thee are parameter to induce pistols and gyro fails.

Torpedoes has max and min random power and damage radius.

It is posible then, you can have a min power with min radius explosion, plus if the torp is magnetic, it detonates at some range of the ship hull, stock is 2m, if not remember bad...

In example, you can have a magnetic pistol detonating at 2m of the hull, and a random explosion with minimun radius of 3m, and min power...

This can be the explanation fro the "No visible damage" of some explosions.

Plus some torps detonates far from the target...

It is souposed, if you "uncheck" the Dud torpedoes options, this mut not happen, but if not remember dad, i have this behaviour evven with "no dud torpedoes" into game options.



With the settings above, we are having an very interesting behaviour... not intended as a grat mod, but the behaviour is so interesting to not share with other simmers.

[UnSalted]

A while back I worked on designing new manufacturing processes for car airbag accelerants (accelerant is politespeak for HE) and go to learn about concussive (sympathetic) explosions versus spark induced fires/explosions. From that, I figured after trying to sink some tankers that whoever designed the game must have put HE shells in the deck guns for good reason since HE's start fires which provide the necessary ignition for any fuel they carry. I've sunk 4 or 5 since then by putting two torps into the beasties and surfacing for 10-15 good 4.5" shots into the deck area. Seems that once they start burning they go down after a fairly short wait.

I'll know more after I sink a few dozen more hopefully.

[Redwine]

Originally Posted by UnSalted

A while back I worked on designing new manufacturing processes for car airbag accelerants (accelerant is politespeak for HE) and go to learn about concussive (sympathetic) explosions versus spark induced fires/explosions. From that, I figured after trying to sink some tankers that whoever designed the game must have put HE shells in the deck guns for good reason since HE's start fires which provide the necessary ignition for any fuel they carry. I've sunk 4 or 5 since then by putting two torps into the beasties and surfacing for 10-15 good 4.5" shots into the deck area. Seems that once they start burning they go down after a fairly short wait.

I'll know more after I sink a few dozen more hopefully.

You are right, not sure if game works as in real life.

For my experience into SH III, the AP and HE shells are the same with diferent power and radius only.

I note into SH IV, the graphic damage showed size is concordant with the radius you adjusted into the file.

I reduced in the mod the torpedo radius to have smaller holes.

But i am not sure, if it is only a graphic effect, or if have any influence on the flooding values.

I had not time to take hands on the shells yet, but suposing the radius as influence on the flooding, i think so... just an idea... the best way may be...

AP (Armor Piercing Shells) :
big radius, small hitpoints, to cause flooding with not too much damage.

HE (High Explosive Shells) :
a] small radius, big hitpoints, to cause more damage with not too much flooding
B] big radius, big hitpoints, to cause more damage and good floding.

Just an idea...

[zylark]

I did a patrol yesterday, and did indeed have the unfortune to hit upon one of the nearly indestructible large tankers. If memory serves me right, I first put two fish into its port side. Started a small fire at the front 1/3, and a whiff of flame at the rear. All well and good I thought. Next target, can deal with this one later.

As I came back, one torp after the other did nothing. Port and Starboard, through the entire length of the hull. I think I at least spent 8 torps that actually hit and detonated on the thing (one dud and one premature, so total would be 10). I finally sank it though. The two last fishes did seem to have an impact so to speak. Well, the last at least. Great ball o'fire.

What I noticed though was that none of them made an actual hole on the side of the tanker. Strange. Could there be something really wrong with the Large tanker damage model?

Later on the same patrol, I located a Task force of Battleships (and surrounding cruisers, DDs, support ships). Took out one such Battleship with my entire front tubes in a salvo (well, you know, not salvo as such, but rapid sequence). With a resulting 5 holes on the side. Capsized and sunk.

When did they start building tankers stronger than battleships?

[RickC Sniper]

Are you guys sure that the "No visible damage" of some torpedo hits isn't just a random thing?

I have the graphics turned on all the way, and after testing with "no dud torpedoes" some of the hits produce visible damage but some do not.

[Redwine]

Originally Posted by RickC Sniper

Are you guys sure that the "No visible damage" of some torpedo hits isn't just a random thing?

I have the graphics turned on all the way, and after testing with "no dud torpedoes" some of the hits produce visible damage but some do not.

Same here... may be the torps need to cross a boundary damage value to trigger the graphic... :hmm:.

[zylark]

Oh, not all impacts will result in a visible hole. Not what I was implying at all. But of 8 hits on a large tanker, I had no visible holes, none. And of 6 hits on a battleship, I got 5 visible holes. (all hits were keel depth/2) So if there is some correlation between damage sustained by an impact (thickness of hull, angle of hit, size of warhead, what have you) and whether or not a hole appears, then that would imply that Large tankers hull is made from extra superduper-strength titanium/composite alloy.

[ccruner13]

when i was assualting a tanker in harbor most of my torps left no visible damage but one made the 'normal' hole however many feet across it is and then one made a really small hole only a handful of feet across. it barely looked like a hole at all... that was the first time id seen anything besides no hole or normal hole and havent since. ive also hit the front of a bb or something so close to the end that it blew the whole front off below the deck so it looked like some toothy beast.

[Redwine]

Some ships seems to be more strong in campaiugn than in a test mission. :hmm:

In example...
You make a test mission, and put a set of ships, same ships, with all the load-up choices of the mission editor.

You adjust hitpoints, torpedo power...bla...bla..bla...

All works fine...

Then you runs a campaing mission, jus a new campaign, not an old campaign, not a saved mission...

When you found this ship... those loaded with fuel, or ammo, have the same behaviour in campaign than into the test mission.

But there are another ships, with no fuel or ammo as load, i know it due to they have not the FX effects for fuel or ammo destroy....

These ships has not the same behaviour than in a test mission, i souposed they was filled-up with freight, as the optioninto the mission editor....

But they had not the same behaviour... they seems to need much more torps than a ship filled with freight into the mission editor...

May be posible they are "empty" ?

May be posible the campaign has more or diferent load up options than a test mission ?

Why this diferent behaviour into those ships, with no ammo, and no fuel as load ?

Those are the strong ships, those seems to be the hard to sink ships.

:hmm::hmm::hmm:

[nattydread]

Originally Posted by Redwine

You are right, not sure if game works as in real life.

For my experience into SH III, the AP and HE shells are the same with diferent power and radius only.

I note into SH IV, the graphic damage showed size is concordant with the radius you adjusted into the file.

I reduced in the mod the torpedo radius to have smaller holes.

But i am not sure, if it is only a graphic effect, or if have any influence on the flooding values.

I had not time to take hands on the shells yet, but suposing the radius as influence on the flooding, i think so... just an idea... the best way may be...

AP (Armor Piercing Shells) :
big radius, small hitpoints, to cause flooding with not too much damage.

HE (High Explosive Shells) :
a] small radius, big hitpoints, to cause more damage with not too much flooding
B] big radius, big hitpoints, to cause more damage and good floding.

Just an idea...

The big question is weither or not AP has any delayed explosive charge in it. But generally AP leaves small holes...it pierces. it only applies is damage to the areas it hits and that area is small. It does however allow it to cause damage to internals, but once again only for those things it hits as it travels through.

HE on the other hand will leaves big holes with lots of damage, but it will be localized only on the hull and a limited interior area near the impact.

Now if the target is armored, the AP does the same thing but with less penetration inside the target, so less internal travel to hit things. HE on an armored target basically does nothing. It just explodes and barely does anything to the target but scorch it.

Imagine a soda can as a merchant. Shot the soda can with a .22...thats AP, place a small fire cracker on the side of the can...thats HE.

Imagine a thin piece of sheet metal. Shoot it with a .22..thats small caliber AP(sub deck gun, DD guns, etc)..it may or may not penetrate, shot it with a .45...thats bigger AP(crusier or BB class guns). Place a small firecracker next to that sheetmetal...thats HE. It will scorch the sheetmetal, if its big enough it may crack the sheetmetal, but in general it doesnt dramtaically impact anything on the other side, it doesnt drasically decrease the structural integerity of the sheetmetal...it wont weaken the ship.

AP stabs, HE blows up. AP expends most of its energy just trying to get through and leaving a small hole roughly the size of the round. HE unleashes its energy in all directions leaving a hole on the hull much significantly bigger than the round.

[Redwine]

Many thanks for explanation.

Sadly... i think so, AP and HE diference is not modellated in the game, they are basically the same shell where you can adjust diferent parameters, damage radius, hitpoints power, speed.

We can play adjusting difrent effects on both, in example a very small radius but high power in AP, and high power but big radius on HE.